Major League Baseball's version of the Draft lottery doesn't attract nearly as much attention as its NBA and NHL counterparts, mostly because baseball's top picks aren't determined randomly like they are in the other sports. But for 12 big league clubs, the Competitive Balance Lottery on Wednesday will provide them with a valuable extra selection in 2015.

Introduced when the current Collective Bargaining Agreement came into play in December 2011, the Competitive Balance Lottery gives teams who have either one of the 10 smallest markets or 10 smallest revenue pools one of six additional choices after each of the first and second rounds. Additionally, any other clubs that are eligible to receive revenue-sharing funds are eligible for the supplemental second-round selections.

This year, the Athletics, Brewers, Cardinals, D-backs, Indians, Marlins, Orioles, Padres, Pirates, Rays, Reds, Rockies and Royals have a shot at the supplemental first-round picks. Whichever teams from that group don't get one of those will be eligible for the supplemental second-rounders, as will the Mariners and Twins. The lottery will be held Wednesday at 2 p.m. ET, at the Commissioner's Office in New York.

The extra selections take on added importance under the revised Draft rules, which assign bonus pools for each club to cover the first 10 rounds and impose the loss of future draft picks if the allotments are exceeded by more than 5 percent. In 2013, the six lottery picks after the first round added an average of $1,484,500 to their teams' pools, while those after the second round augmented their clubs by an average of $790,350.

Competitive Balance Lottery picks have been part of the Draft for only two years, but they've already produced one Major Leaguer. The Tigers selected Corey Knebel 39th overall in June 2013 and signed him for $1,433,400. He made his big league debut on May 24.

Detroit acquired the choice it used on Knebel via a trade, highlighting something unique about the Competitive Balance Lottery. The dozen selections it creates are the only Draft selections permitted to change hands. Teams can deal the lottery choices, subject to some restrictions.

Each lottery pick can be traded only once and cash can't be involved in the transaction. The choices can be dealt only during the regular season, up until 5 p.m. ET, on the first day of the Draft.

The Tigers and Marlins made the first-ever Draft pick trade in July 2012. Detroit acquired Omar Infante and Anibal Sanchez from Miami in exchange for prospects Rob Brantly, Brian Flynn and Jacob Turner. Additionally, the Marlins swapped their Lottery choice after the first round (which became Knebel) for the Tigers' after the second.

There have been three other deals involving Draft selections. Also in July 2012, the Pirates traded Gorkys Hernandez and a supplemental first-rounder to the Marlins for Gaby Sanchez and Minor Leaguer Kyle Kaminska.

In July 2013, the Orioles sent prospects Josh Hader and L.J. Hoes and a supplemental first-rounder to the Astros for Bud Norris and an international bonus slot. Miami was involved in a third draft-pick trade this June, when it gave up a supplemental first-rounder to Pittsburgh for Bryan Morris.

The Royals are the only team to win Competitive Balance choices after the first round in each of the first two lotteries. They were awarded the top pick (No. 34) in 2013, which they used on left-hander Sean Manaea, who currently ranks 94th on MLBPipeline.com's Top 100 Prospects list. Kansas City also received the No. 40 selection in 2014 and tabbed catcher Chase Vallot.

Jim Callis is a reporter for MLB.com and writes a blog, Callis' Corner. Follow @jimcallisMLB on Twitter. This story was not subject to the approval of Major League Baseball or its clubs. This story was not subject to the approval of Major League Baseball or its clubs.